A plug connector part may include at least one electrical contact element for carrying an electrical current and for establishing electrical contact with at least one other contact element of a mating plug connector part, and a temperature sensor device for recording a rise in temperature of the plug connector part.
A plug connector part of this type can be used in particular on a charging device for transmitting a charging current. The plug connector part can in particular be formed as a charging plug for charging a motor vehicle driven by an electric motor (also referred to as an electric vehicle).
Charging plugs for charging electric vehicles are designed such that large charging currents can be transmitted. Since the thermal loss power increases quadratically with the charging current, the temperature of such charging plugs needs to be monitored in order to identify in good time when components of the charging plug are overheating and to modify the charging current or even to switch off the charging device if necessary.
In a charging plug known from EP 2 605 339 A1, a temperature sensor is arranged on an insulating body, approximately centrally between contact elements of the contact plug. The temperature sensor makes it possible to identify whether there is an excessive rise in temperature anywhere on the contact elements, in order to stop the charging process if necessary.
In a charging plug known from GB 2 489 988 A, a plurality of temperature sensors are provided which communicate temperature data via a line. A charging process is controlled depending on the temperature range in which the temperatures recorded at the temperature sensors lie.
U.S. Pat. No. 6,210,036 B1 discloses a plug connector, in which a plurality of temperature sensors are interlinked in series by means of a single-core line. The temperature sensors are arranged on an insulating body and have a significant change in resistance at a pre-determined temperature that is of such a degree that a control circuit connected to the line can detect the change and adapt the current flowing through the charging plug, cutting it off if necessary.
U.S. Pat. No. 8,325,454 B2 discloses a plug, in which individual contacts are associated with thermistors which are interconnected in parallel and conductively switch a thyristor when a threshold temperature is exceeded in order to thus switch off a current flowing through the contacts.
In charging plugs known from the prior art, temperature sensors are in particular embedded in an insulating body. This is required for electrically insulating the temperature sensors from the contact elements, the temperature of which may increase. However, this simultaneously entails the disadvantage that a change in temperature of one of the contact elements is transmitted via the insulating body with a time delay and is therefore sensed at the temperature sensors with a time delay. Particularly in concepts which are intended to make it possible to quickly disconnect a load circuit in the event of a fault, such temperature sensor arrangements are therefore sometimes unsuitable.